lossless_neon: harmonize function suffixes
lossless_neon: harmonize function suffixes

BUG=webp:355

Change-Id: I4210081a39800b5c2589c443da237269908af666

webmproject/libwebp,PKRoma/libwebp,PKRoma/libwebp,PKRoma/libwebp,PKRoma/libwebp,PKRoma/libwebp,webmproject/libwebp,webmproject/libwebp,webmproject/libwebp,PKRoma/libwebp,webmproject/libwebp